An assessment on removal performance of arsenic with treated Turbinaria vulgaris as an adsorbent: Characterization, optimization, isotherm, and kinetics study

In this current research, batch experiments were performed toward the characterization and optimization of arsenic removal by Turbinaria vulgaris. The four process parameters, that is, initial solution pH (3-5), initial arsenic ion concentration (20-100 mg/L), T. vulgaris dosage (0.10.5 g/L), and temperature (293-313 K), were considered for the process optimization through response surface methodology via central composite design (CCD) approach. According to CCD methodology, a set of 30 experimental runs were conducted and the results were analyzed; the suggested quadratic model has well matched to the experimental results which might be used to design space according to the study of analysis of variance. The highest removal efficiency of 92.12% was attained, retaining the process conditions viz. pH 4.41, biomass dosage 0.3 g/L, initial arsenic concentration 21.33 mg/L, and temperature 298.32 K. Biosorbent morphology and chemical properties were characterized by means of fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analysis. The presence of metal ions in the biomass of T. vulgaris after biosorption was confirmed from the SEM result. These results are significant toward the assessment and optimization of removal of arsenic ions by T. vulgaris biomass. To estimate the solute interaction and biosorption nature, the experimental data were verified with different isotherms and kinetic models. The results discovered that T. vulgaris could be a cost-effective and eco-friendly biosorbent for the removal of arsenic ions.